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;
; jidctint.asm - accurate integer IDCT (64-bit AVX2)
;
; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
; Copyright (C) 2009, 2016, 2018, 2020, D. R. Commander.
; Copyright (C) 2018, Matthias Räncker.
;
; Based on the x86 SIMD extension for IJG JPEG library
; Copyright (C) 1999-2006, MIYASAKA Masaru.
; For conditions of distribution and use, see copyright notice in jsimdext.inc
;
; This file should be assembled with NASM (Netwide Assembler),
; can *not* be assembled with Microsoft's MASM or any compatible
; assembler (including Borland's Turbo Assembler).
; NASM is available from http://nasm.sourceforge.net/ or
; http://sourceforge.net/project/showfiles.php?group_id=6208
;
; This file contains a slower but more accurate integer implementation of the
; inverse DCT (Discrete Cosine Transform). The following code is based
; directly on the IJG's original jidctint.c; see the jidctint.c for
; more details.
%include "jsimdext.inc"
%include "jdct.inc"
; --------------------------------------------------------------------------
%define CONST_BITS 13
%define PASS1_BITS 2
%define DESCALE_P1 (CONST_BITS - PASS1_BITS)
%define DESCALE_P2 (CONST_BITS + PASS1_BITS + 3)
%if CONST_BITS == 13
F_0_298 equ 2446 ; FIX(0.298631336)
F_0_390 equ 3196 ; FIX(0.390180644)
F_0_541 equ 4433 ; FIX(0.541196100)
F_0_765 equ 6270 ; FIX(0.765366865)
F_0_899 equ 7373 ; FIX(0.899976223)
F_1_175 equ 9633 ; FIX(1.175875602)
F_1_501 equ 12299 ; FIX(1.501321110)
F_1_847 equ 15137 ; FIX(1.847759065)
F_1_961 equ 16069 ; FIX(1.961570560)
F_2_053 equ 16819 ; FIX(2.053119869)
F_2_562 equ 20995 ; FIX(2.562915447)
F_3_072 equ 25172 ; FIX(3.072711026)
%else
; NASM cannot do compile-time arithmetic on floating-point constants.
%define DESCALE(x, n) (((x) + (1 << ((n) - 1))) >> (n))
F_0_298 equ DESCALE( 320652955, 30 - CONST_BITS) ; FIX(0.298631336)
F_0_390 equ DESCALE( 418953276, 30 - CONST_BITS) ; FIX(0.390180644)
F_0_541 equ DESCALE( 581104887, 30 - CONST_BITS) ; FIX(0.541196100)
F_0_765 equ DESCALE( 821806413, 30 - CONST_BITS) ; FIX(0.765366865)
F_0_899 equ DESCALE( 966342111, 30 - CONST_BITS) ; FIX(0.899976223)
F_1_175 equ DESCALE(1262586813, 30 - CONST_BITS) ; FIX(1.175875602)
F_1_501 equ DESCALE(1612031267, 30 - CONST_BITS) ; FIX(1.501321110)
F_1_847 equ DESCALE(1984016188, 30 - CONST_BITS) ; FIX(1.847759065)
F_1_961 equ DESCALE(2106220350, 30 - CONST_BITS) ; FIX(1.961570560)
F_2_053 equ DESCALE(2204520673, 30 - CONST_BITS) ; FIX(2.053119869)
F_2_562 equ DESCALE(2751909506, 30 - CONST_BITS) ; FIX(2.562915447)
F_3_072 equ DESCALE(3299298341, 30 - CONST_BITS) ; FIX(3.072711026)
%endif
; --------------------------------------------------------------------------
; In-place 8x8x16-bit inverse matrix transpose using AVX2 instructions
; %1-%4: Input/output registers
; %5-%8: Temp registers
%macro dotranspose 8
; %5=(00 10 20 30 40 50 60 70 01 11 21 31 41 51 61 71)
; %6=(03 13 23 33 43 53 63 73 02 12 22 32 42 52 62 72)
; %7=(04 14 24 34 44 54 64 74 05 15 25 35 45 55 65 75)
; %8=(07 17 27 37 47 57 67 77 06 16 26 36 46 56 66 76)
vpermq %5, %1, 0xD8
vpermq %6, %2, 0x72
vpermq %7, %3, 0xD8
vpermq %8, %4, 0x72
; transpose coefficients(phase 1)
; %5=(00 10 20 30 01 11 21 31 40 50 60 70 41 51 61 71)
; %6=(02 12 22 32 03 13 23 33 42 52 62 72 43 53 63 73)
; %7=(04 14 24 34 05 15 25 35 44 54 64 74 45 55 65 75)
; %8=(06 16 26 36 07 17 27 37 46 56 66 76 47 57 67 77)
vpunpcklwd %1, %5, %6
vpunpckhwd %2, %5, %6
vpunpcklwd %3, %7, %8
vpunpckhwd %4, %7, %8
; transpose coefficients(phase 2)
; %1=(00 02 10 12 20 22 30 32 40 42 50 52 60 62 70 72)
; %2=(01 03 11 13 21 23 31 33 41 43 51 53 61 63 71 73)
; %3=(04 06 14 16 24 26 34 36 44 46 54 56 64 66 74 76)
; %4=(05 07 15 17 25 27 35 37 45 47 55 57 65 67 75 77)
vpunpcklwd %5, %1, %2
vpunpcklwd %6, %3, %4
vpunpckhwd %7, %1, %2
vpunpckhwd %8, %3, %4
; transpose coefficients(phase 3)
; %5=(00 01 02 03 10 11 12 13 40 41 42 43 50 51 52 53)
; %6=(04 05 06 07 14 15 16 17 44 45 46 47 54 55 56 57)
; %7=(20 21 22 23 30 31 32 33 60 61 62 63 70 71 72 73)
; %8=(24 25 26 27 34 35 36 37 64 65 66 67 74 75 76 77)
vpunpcklqdq %1, %5, %6
vpunpckhqdq %2, %5, %6
vpunpcklqdq %3, %7, %8
vpunpckhqdq %4, %7, %8
; transpose coefficients(phase 4)
; %1=(00 01 02 03 04 05 06 07 40 41 42 43 44 45 46 47)
; %2=(10 11 12 13 14 15 16 17 50 51 52 53 54 55 56 57)
; %3=(20 21 22 23 24 25 26 27 60 61 62 63 64 65 66 67)
; %4=(30 31 32 33 34 35 36 37 70 71 72 73 74 75 76 77)
%endmacro
; --------------------------------------------------------------------------
; In-place 8x8x16-bit accurate integer inverse DCT using AVX2 instructions
; %1-%4: Input/output registers
; %5-%12: Temp registers
; %9: Pass (1 or 2)
%macro dodct 13
; -- Even part
; (Original)
; z1 = (z2 + z3) * 0.541196100;
; tmp2 = z1 + z3 * -1.847759065;
; tmp3 = z1 + z2 * 0.765366865;
;
; (This implementation)
; tmp2 = z2 * 0.541196100 + z3 * (0.541196100 - 1.847759065);
; tmp3 = z2 * (0.541196100 + 0.765366865) + z3 * 0.541196100;
vperm2i128 %6, %3, %3, 0x01 ; %6=in6_2
vpunpcklwd %5, %3, %6 ; %5=in26_62L
vpunpckhwd %6, %3, %6 ; %6=in26_62H
vpmaddwd %5, %5, [rel PW_F130_F054_MF130_F054] ; %5=tmp3_2L
vpmaddwd %6, %6, [rel PW_F130_F054_MF130_F054] ; %6=tmp3_2H
vperm2i128 %7, %1, %1, 0x01 ; %7=in4_0
vpsignw %1, %1, [rel PW_1_NEG1]
vpaddw %7, %7, %1 ; %7=(in0+in4)_(in0-in4)
vpxor %1, %1, %1
vpunpcklwd %8, %1, %7 ; %8=tmp0_1L
vpunpckhwd %1, %1, %7 ; %1=tmp0_1H
vpsrad %8, %8, (16-CONST_BITS) ; vpsrad %8,16 & vpslld %8,CONST_BITS
vpsrad %1, %1, (16-CONST_BITS) ; vpsrad %1,16 & vpslld %1,CONST_BITS
vpsubd %11, %8, %5 ; %11=tmp0_1L-tmp3_2L=tmp13_12L
vpaddd %9, %8, %5 ; %9=tmp0_1L+tmp3_2L=tmp10_11L
vpsubd %12, %1, %6 ; %12=tmp0_1H-tmp3_2H=tmp13_12H
vpaddd %10, %1, %6 ; %10=tmp0_1H+tmp3_2H=tmp10_11H
; -- Odd part
vpaddw %1, %4, %2 ; %1=in7_5+in3_1=z3_4
; (Original)
; z5 = (z3 + z4) * 1.175875602;
; z3 = z3 * -1.961570560; z4 = z4 * -0.390180644;
; z3 += z5; z4 += z5;
;
; (This implementation)
; z3 = z3 * (1.175875602 - 1.961570560) + z4 * 1.175875602;
; z4 = z3 * 1.175875602 + z4 * (1.175875602 - 0.390180644);
vperm2i128 %8, %1, %1, 0x01 ; %8=z4_3
vpunpcklwd %7, %1, %8 ; %7=z34_43L
vpunpckhwd %8, %1, %8 ; %8=z34_43H
vpmaddwd %7, %7, [rel PW_MF078_F117_F078_F117] ; %7=z3_4L
vpmaddwd %8, %8, [rel PW_MF078_F117_F078_F117] ; %8=z3_4H
; (Original)
; z1 = tmp0 + tmp3; z2 = tmp1 + tmp2;
; tmp0 = tmp0 * 0.298631336; tmp1 = tmp1 * 2.053119869;
; tmp2 = tmp2 * 3.072711026; tmp3 = tmp3 * 1.501321110;
; z1 = z1 * -0.899976223; z2 = z2 * -2.562915447;
; tmp0 += z1 + z3; tmp1 += z2 + z4;
; tmp2 += z2 + z3; tmp3 += z1 + z4;
;
; (This implementation)
; tmp0 = tmp0 * (0.298631336 - 0.899976223) + tmp3 * -0.899976223;
; tmp1 = tmp1 * (2.053119869 - 2.562915447) + tmp2 * -2.562915447;
; tmp2 = tmp1 * -2.562915447 + tmp2 * (3.072711026 - 2.562915447);
; tmp3 = tmp0 * -0.899976223 + tmp3 * (1.501321110 - 0.899976223);
; tmp0 += z3; tmp1 += z4;
; tmp2 += z3; tmp3 += z4;
vperm2i128 %2, %2, %2, 0x01 ; %2=in1_3
vpunpcklwd %3, %4, %2 ; %3=in71_53L
vpunpckhwd %4, %4, %2 ; %4=in71_53H
vpmaddwd %5, %3, [rel PW_MF060_MF089_MF050_MF256] ; %5=tmp0_1L
vpmaddwd %6, %4, [rel PW_MF060_MF089_MF050_MF256] ; %6=tmp0_1H
vpaddd %5, %5, %7 ; %5=tmp0_1L+z3_4L=tmp0_1L
vpaddd %6, %6, %8 ; %6=tmp0_1H+z3_4H=tmp0_1H
vpmaddwd %3, %3, [rel PW_MF089_F060_MF256_F050] ; %3=tmp3_2L
vpmaddwd %4, %4, [rel PW_MF089_F060_MF256_F050] ; %4=tmp3_2H
vperm2i128 %7, %7, %7, 0x01 ; %7=z4_3L
vperm2i128 %8, %8, %8, 0x01 ; %8=z4_3H
vpaddd %7, %3, %7 ; %7=tmp3_2L+z4_3L=tmp3_2L
vpaddd %8, %4, %8 ; %8=tmp3_2H+z4_3H=tmp3_2H
; -- Final output stage
vpaddd %1, %9, %7 ; %1=tmp10_11L+tmp3_2L=data0_1L
vpaddd %2, %10, %8 ; %2=tmp10_11H+tmp3_2H=data0_1H
vpaddd %1, %1, [rel PD_DESCALE_P %+ %13]
vpaddd %2, %2, [rel PD_DESCALE_P %+ %13]
vpsrad %1, %1, DESCALE_P %+ %13
vpsrad %2, %2, DESCALE_P %+ %13
vpackssdw %1, %1, %2 ; %1=data0_1
vpsubd %3, %9, %7 ; %3=tmp10_11L-tmp3_2L=data7_6L
vpsubd %4, %10, %8 ; %4=tmp10_11H-tmp3_2H=data7_6H
vpaddd %3, %3, [rel PD_DESCALE_P %+ %13]
vpaddd %4, %4, [rel PD_DESCALE_P %+ %13]
vpsrad %3, %3, DESCALE_P %+ %13
vpsrad %4, %4, DESCALE_P %+ %13
vpackssdw %4, %3, %4 ; %4=data7_6
vpaddd %7, %11, %5 ; %7=tmp13_12L+tmp0_1L=data3_2L
vpaddd %8, %12, %6 ; %8=tmp13_12H+tmp0_1H=data3_2H
vpaddd %7, %7, [rel PD_DESCALE_P %+ %13]
vpaddd %8, %8, [rel PD_DESCALE_P %+ %13]
vpsrad %7, %7, DESCALE_P %+ %13
vpsrad %8, %8, DESCALE_P %+ %13
vpackssdw %2, %7, %8 ; %2=data3_2
vpsubd %7, %11, %5 ; %7=tmp13_12L-tmp0_1L=data4_5L
vpsubd %8, %12, %6 ; %8=tmp13_12H-tmp0_1H=data4_5H
vpaddd %7, %7, [rel PD_DESCALE_P %+ %13]
vpaddd %8, %8, [rel PD_DESCALE_P %+ %13]
vpsrad %7, %7, DESCALE_P %+ %13
vpsrad %8, %8, DESCALE_P %+ %13
vpackssdw %3, %7, %8 ; %3=data4_5
%endmacro
; --------------------------------------------------------------------------
SECTION SEG_CONST
alignz 32
GLOBAL_DATA(jconst_idct_islow_avx2)
EXTN(jconst_idct_islow_avx2):
PW_F130_F054_MF130_F054 times 4 dw (F_0_541 + F_0_765), F_0_541
times 4 dw (F_0_541 - F_1_847), F_0_541
PW_MF078_F117_F078_F117 times 4 dw (F_1_175 - F_1_961), F_1_175
times 4 dw (F_1_175 - F_0_390), F_1_175
PW_MF060_MF089_MF050_MF256 times 4 dw (F_0_298 - F_0_899), -F_0_899
times 4 dw (F_2_053 - F_2_562), -F_2_562
PW_MF089_F060_MF256_F050 times 4 dw -F_0_899, (F_1_501 - F_0_899)
times 4 dw -F_2_562, (F_3_072 - F_2_562)
PD_DESCALE_P1 times 8 dd 1 << (DESCALE_P1 - 1)
PD_DESCALE_P2 times 8 dd 1 << (DESCALE_P2 - 1)
PB_CENTERJSAMP times 32 db CENTERJSAMPLE
PW_1_NEG1 times 8 dw 1
times 8 dw -1
alignz 32
; --------------------------------------------------------------------------
SECTION SEG_TEXT
BITS 64
;
; Perform dequantization and inverse DCT on one block of coefficients.
;
; GLOBAL(void)
; jsimd_idct_islow_avx2(void *dct_table, JCOEFPTR coef_block,
; JSAMPARRAY output_buf, JDIMENSION output_col)
;
; r10 = jpeg_component_info *compptr
; r11 = JCOEFPTR coef_block
; r12 = JSAMPARRAY output_buf
; r13d = JDIMENSION output_col
align 32
GLOBAL_FUNCTION(jsimd_idct_islow_avx2)
EXTN(jsimd_idct_islow_avx2):
push rbp
mov rax, rsp ; rax = original rbp
mov rbp, rsp ; rbp = aligned rbp
push_xmm 4
collect_args 4
; ---- Pass 1: process columns.
%ifndef NO_ZERO_COLUMN_TEST_ISLOW_AVX2
mov eax, dword [DWBLOCK(1,0,r11,SIZEOF_JCOEF)]
or eax, dword [DWBLOCK(2,0,r11,SIZEOF_JCOEF)]
jnz near .columnDCT
movdqa xmm0, XMMWORD [XMMBLOCK(1,0,r11,SIZEOF_JCOEF)]
movdqa xmm1, XMMWORD [XMMBLOCK(2,0,r11,SIZEOF_JCOEF)]
vpor xmm0, xmm0, XMMWORD [XMMBLOCK(3,0,r11,SIZEOF_JCOEF)]
vpor xmm1, xmm1, XMMWORD [XMMBLOCK(4,0,r11,SIZEOF_JCOEF)]
vpor xmm0, xmm0, XMMWORD [XMMBLOCK(5,0,r11,SIZEOF_JCOEF)]
vpor xmm1, xmm1, XMMWORD [XMMBLOCK(6,0,r11,SIZEOF_JCOEF)]
vpor xmm0, xmm0, XMMWORD [XMMBLOCK(7,0,r11,SIZEOF_JCOEF)]
vpor xmm1, xmm1, xmm0
vpacksswb xmm1, xmm1, xmm1
vpacksswb xmm1, xmm1, xmm1
movd eax, xmm1
test rax, rax
jnz short .columnDCT
; -- AC terms all zero
movdqa xmm5, XMMWORD [XMMBLOCK(0,0,r11,SIZEOF_JCOEF)]
vpmullw xmm5, xmm5, XMMWORD [XMMBLOCK(0,0,r10,SIZEOF_ISLOW_MULT_TYPE)]
vpsllw xmm5, xmm5, PASS1_BITS
vpunpcklwd xmm4, xmm5, xmm5 ; xmm4=(00 00 01 01 02 02 03 03)
vpunpckhwd xmm5, xmm5, xmm5 ; xmm5=(04 04 05 05 06 06 07 07)
vinserti128 ymm4, ymm4, xmm5, 1
vpshufd ymm0, ymm4, 0x00 ; ymm0=col0_4=(00 00 00 00 00 00 00 00 04 04 04 04 04 04 04 04)
vpshufd ymm1, ymm4, 0x55 ; ymm1=col1_5=(01 01 01 01 01 01 01 01 05 05 05 05 05 05 05 05)
vpshufd ymm2, ymm4, 0xAA ; ymm2=col2_6=(02 02 02 02 02 02 02 02 06 06 06 06 06 06 06 06)
vpshufd ymm3, ymm4, 0xFF ; ymm3=col3_7=(03 03 03 03 03 03 03 03 07 07 07 07 07 07 07 07)
jmp near .column_end
%endif
.columnDCT:
vmovdqu ymm4, YMMWORD [YMMBLOCK(0,0,r11,SIZEOF_JCOEF)] ; ymm4=in0_1
vmovdqu ymm5, YMMWORD [YMMBLOCK(2,0,r11,SIZEOF_JCOEF)] ; ymm5=in2_3
vmovdqu ymm6, YMMWORD [YMMBLOCK(4,0,r11,SIZEOF_JCOEF)] ; ymm6=in4_5
vmovdqu ymm7, YMMWORD [YMMBLOCK(6,0,r11,SIZEOF_JCOEF)] ; ymm7=in6_7
vpmullw ymm4, ymm4, YMMWORD [YMMBLOCK(0,0,r10,SIZEOF_ISLOW_MULT_TYPE)]
vpmullw ymm5, ymm5, YMMWORD [YMMBLOCK(2,0,r10,SIZEOF_ISLOW_MULT_TYPE)]
vpmullw ymm6, ymm6, YMMWORD [YMMBLOCK(4,0,r10,SIZEOF_ISLOW_MULT_TYPE)]
vpmullw ymm7, ymm7, YMMWORD [YMMBLOCK(6,0,r10,SIZEOF_ISLOW_MULT_TYPE)]
vperm2i128 ymm0, ymm4, ymm6, 0x20 ; ymm0=in0_4
vperm2i128 ymm1, ymm5, ymm4, 0x31 ; ymm1=in3_1
vperm2i128 ymm2, ymm5, ymm7, 0x20 ; ymm2=in2_6
vperm2i128 ymm3, ymm7, ymm6, 0x31 ; ymm3=in7_5
dodct ymm0, ymm1, ymm2, ymm3, ymm4, ymm5, ymm6, ymm7, ymm8, ymm9, ymm10, ymm11, 1
; ymm0=data0_1, ymm1=data3_2, ymm2=data4_5, ymm3=data7_6
dotranspose ymm0, ymm1, ymm2, ymm3, ymm4, ymm5, ymm6, ymm7
; ymm0=data0_4, ymm1=data1_5, ymm2=data2_6, ymm3=data3_7
.column_end:
; -- Prefetch the next coefficient block
prefetchnta [r11 + DCTSIZE2*SIZEOF_JCOEF + 0*32]
prefetchnta [r11 + DCTSIZE2*SIZEOF_JCOEF + 1*32]
prefetchnta [r11 + DCTSIZE2*SIZEOF_JCOEF + 2*32]
prefetchnta [r11 + DCTSIZE2*SIZEOF_JCOEF + 3*32]
; ---- Pass 2: process rows.
vperm2i128 ymm4, ymm3, ymm1, 0x31 ; ymm3=in7_5
vperm2i128 ymm1, ymm3, ymm1, 0x20 ; ymm1=in3_1
dodct ymm0, ymm1, ymm2, ymm4, ymm3, ymm5, ymm6, ymm7, ymm8, ymm9, ymm10, ymm11, 2
; ymm0=data0_1, ymm1=data3_2, ymm2=data4_5, ymm4=data7_6
dotranspose ymm0, ymm1, ymm2, ymm4, ymm3, ymm5, ymm6, ymm7
; ymm0=data0_4, ymm1=data1_5, ymm2=data2_6, ymm4=data3_7
vpacksswb ymm0, ymm0, ymm1 ; ymm0=data01_45
vpacksswb ymm1, ymm2, ymm4 ; ymm1=data23_67
vpaddb ymm0, ymm0, [rel PB_CENTERJSAMP]
vpaddb ymm1, ymm1, [rel PB_CENTERJSAMP]
vextracti128 xmm6, ymm1, 1 ; xmm3=data67
vextracti128 xmm4, ymm0, 1 ; xmm2=data45
vextracti128 xmm2, ymm1, 0 ; xmm1=data23
vextracti128 xmm0, ymm0, 0 ; xmm0=data01
vpshufd xmm1, xmm0, 0x4E ; xmm1=(10 11 12 13 14 15 16 17 00 01 02 03 04 05 06 07)
vpshufd xmm3, xmm2, 0x4E ; xmm3=(30 31 32 33 34 35 36 37 20 21 22 23 24 25 26 27)
vpshufd xmm5, xmm4, 0x4E ; xmm5=(50 51 52 53 54 55 56 57 40 41 42 43 44 45 46 47)
vpshufd xmm7, xmm6, 0x4E ; xmm7=(70 71 72 73 74 75 76 77 60 61 62 63 64 65 66 67)
vzeroupper
mov eax, r13d
mov rdxp, JSAMPROW [r12+0*SIZEOF_JSAMPROW] ; (JSAMPLE *)
mov rsip, JSAMPROW [r12+1*SIZEOF_JSAMPROW] ; (JSAMPLE *)
movq XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm0
movq XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm1
mov rdxp, JSAMPROW [r12+2*SIZEOF_JSAMPROW] ; (JSAMPLE *)
mov rsip, JSAMPROW [r12+3*SIZEOF_JSAMPROW] ; (JSAMPLE *)
movq XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm2
movq XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm3
mov rdxp, JSAMPROW [r12+4*SIZEOF_JSAMPROW] ; (JSAMPLE *)
mov rsip, JSAMPROW [r12+5*SIZEOF_JSAMPROW] ; (JSAMPLE *)
movq XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm4
movq XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm5
mov rdxp, JSAMPROW [r12+6*SIZEOF_JSAMPROW] ; (JSAMPLE *)
mov rsip, JSAMPROW [r12+7*SIZEOF_JSAMPROW] ; (JSAMPLE *)
movq XMM_MMWORD [rdx+rax*SIZEOF_JSAMPLE], xmm6
movq XMM_MMWORD [rsi+rax*SIZEOF_JSAMPLE], xmm7
uncollect_args 4
pop_xmm 4
pop rbp
ret
; For some reason, the OS X linker does not honor the request to align the
; segment unless we do this.
align 32